You’ve seen these errors. So painful.

• Make sure the disk is not full or write-protected and that the file is not currently in use.
• Cannot delete file: Access is denied.
• The file is in use by another program or user.
• There has been a sharing violation.
• The source or destination file may be in use.

How many times have you seen this error? At least windows should tell you, who is locking the file, right?
First trying to find out why the file is locked. If it is spyware or a critical process, you may want to know that such a problem exists.
A more powerful version of this is actually unlocker than will allow you to kill the processes that are locking file file and delete them automatically.